I live in a Texas county that puts an annual use tax on any aircraft registered to an entity of any kind. Even if it's two friends who set up a corporation or LLC just for liability reasons with strictly personal use. No affidavit mentioned. If the aircraft is registered in an individual's name or is co-owned by individuals there is no annual use tax. Even if a single-seat experimental Pitts is registered to Frank And Harry, LLC our local Central Appraisal District classifies it as commercial just because of the "LLC". It's Experimental without authority to be used commercially. It's one seat day VFR airplane the size of a Volkswagen with a 15 gallon tank for crying out loud. I have many friends who have moved their aircraft to NM airports because of this. I sure would like to see one of those affidavits from Wichita Falls area.
In Texas aircraft sales are not subject to sales tax unless the seller makes his living selling aircraft. What's known as an "occasional sale" is exempt. So if you purchase an aircraft from Joe the Plumber or even Exxon Mobile in Houston, no sales tax. If you purchase an aircraft from Van Bortel in Arlington it triggers sales tax. Because Van Bortel is an aircraft broker and that's their business. Same thing if you purchased an aircraft from Cutter in Deer Valley, AZ and bring it to Texas. Texas will want sales tax because Cutter is a dealer despite being in AZ.
So no worries with sales tax if you bought the airplane out of state prior to moving. Or bought it from an individual whether Texan or otherwise. Or from an entity anywhere who doesn't make aircraft sales a part of their normal course of business. And the mere fact you are military in Wichita Falls will garner a large modicum of respect with the good folks who live there. As well it should.
Jim